CD20 and Outcome of Childhood Precursor B-cell Acute Lymphoblastic Leukemia

Abstract

CD20 is a B-cell differentiation antigen that is expressed variably in precursor B-cell acute lymphoblastic leukemia (BCP-ALL). The prognostic significance of CD20 expression in childhood BCP-ALL remains controversial. Some studies have demonstrated that CD20 overexpression correlates with worse survival in pediatric patients with BCP-ALL, but some other studies suggest a better outcome. To explore the prognostic role of high CD20 expression in pediatric BCP-ALL, we performed a meta-analysis of the previous studies that provided survival information according to CD20 expression status. Pooled hazard ratios (HRs) indicated that high CD20 expression had no inferior impact on the prognosis of pediatric BCP-ALL. The summary HR for overall survival was 0.70 and combined HR for event-free survival was 1.01. These findings suggest that high CD20 expression does not influence the outcome for pediatric BCP-ALL. CD20 may lack prognostic value in children with BCP-ALL.

Commonly Assessed Markers in Childhood BCP-ALL Diagnostic Panels and Their Association with Genetic Aberrations and Outcome Prediction

“…Strong expression of CD20 is more typical for B-cell lymphomas and Burkitt lymphomas than ALL [ 9 , 54 ]. In BCP-ALL blasts have often only partial or low expression of CD20 which, however, may increase during the treatment (particularly in the steroid therapy stage) [ 36 ].…”

“…In adult BCP-ALL cases, the expression of CD20 is associated with poor prognosis and higher risk of relapse. However, in pediatric BCP-ALL there is no clear evidence of CD20 impacting the disease outcome [ 54 ]. Still, some researchers report that (over)expression of CD20 could be associated with t(9;22)— BCR::ABL1 genotype and can be useful to exclude KMT2A gene rearrangement even when expressed at low levels [ 32 ].…”

Prognostic Significance of CD20 Expression in Children with Philadelphia Chromosome-Negative B-Cell Precursor Acute Lymphoblastic Leukemia

“…Jeha et al [8] found that the CD20-positive group tended to have a better survival outcome, though not significantly different from the CD20-negative group. Ou et al [5] and Naithani et al [9, 10] reported that CD20 had no prognostic value in children with BCP-ALL. Moreover, our study with a relatively larger sample also supported that CD20 was not an independent factor affecting the long-term survival of pediatric BCP-ALL patients.…”

“…Although most studies have shown that CD20 expression is a poor prognostic factor in adult B-ALL [6], little is known about its significance in pediatric BCP-ALL [5]. The significance of adding anti-CD20 therapy in pediatric B-ALL remains unknown.…”

“…CD20 is a B lymphocyte-specific surface antigen that is widely expressed in all stages of normal and malignantly differentiated B cells other than stem and plasma cells, and it regulates cell differentiation and apoptosis through downstream signaling pathways [2, 3]. Nearly half of pediatric B-cell precursor (BCP)-ALL leukemic cells express CD20 [4, 5].…”